Hemmed seam and process of producing the same



KL NLAIEF? HEMMED SEAM AND PROCESS OF PRODUCING THE SAME Nov.. 19, 1929.

Filed June l3, 1925 2 Sheets-Sheet l Nov. 19, 1929. K. MAIER 1,736,453

HEMMED SEAM AND PROCESS OF PRODUCING THE SAME Filed June 13; 1925ZSheets-Sheet 2 atented Nov. 19 1929 if UNlTiED STATES @FFICE KARLMAIER, F STUTTGART, GERMANY, ASSIGNOR- TO UNION SPECIAL MASCHINEN-FABRIK, G. M. B. 1-1., 012' STUTTGART, GERMANY HEMMED SEAM AND PROCESSOF PRODUCING THE SAME Application filed June 13, 1925, Serial No.36,887, and. in Germany June 18, 1924.

This invention relates to new and useful improvements in hemmed seamsand the process and machine for making the same, and more particularlyto a hemmed seam which is formed at the edge of a fabric for cover ingthe edge portion thereof.

Prior to this invention hemmed seams have been formed at the edge offabric sections wherein a needle thread has been used to penetrate thefabric and this needle is concatenated with upper and lower coveringthreads. In hemmed seams of the above type the edge of the fabric isoften folded and lies within the covering threads and when the hemmedseam is so formed the inturned edge of the material often penetrates orprotrudes through the covering threads.

An object of the present invention is to provide a hemmed seam whereinseveral sets of covering threads are used and secured by the needlethread in such a way that the portions of the fabric within the limitsof the covering seam are more completely covered and hidden by saidthreads.

It has also been found where achemmed seam is made in the well knownmanner and only one penetrating needle thread used that there isliability of the seam pulling out, and this is particularly true wherethe portion of the fabric turned within the hemmed seam is,

Very narrow. 1

A further object of the invention is to provide a hemmed seam which hasformed there with anchoring covering threads which are tied to thematerial being formed with the hemmedseam by an inner row of penetratingloopers.

A further object of the invention is to pro-' vide a process for forminga seam wherein the covering threads of the same are laid in groups ornested on one face of the material and are secured to the material byloops passing through the nested loop and through the material and bybeing interlocked at the edge of the material with the loops whichpenetrate the material.

A further object of the invention is to provide a process for forminghemmed seams wherein the upper thread carrying looper is provided with aplurality of eyes arranged in groups for independent covering threads sothat said looper when cooperating with a single needle will cause thecovering threads to be laid side by side in groups which moreefficiently cover the portion of the fabric on which such coveringthreads are laid.

A further object of the invention is to provide a process for forming ahemmed seam of the above type wherein the looper is provided with anadditional thread eye adjacent the point thereof with which anotherneedle is adapted to cooperate so as to bind and anchor the coveringthreads.

A further object of the invention is to provide a machine for forming ahemmed seam of the above character with a throat plate which has stitchtongues removably connected to said throat plate in such a manner thatsaid tongues can be adjusted in the direction of the feed.

In the drawings Figure 1 is a perspective view of the upper portion of ahemmed seam containing the invention;

Figure 2 is a similarview of a slightly modified form of hemmed seam;

Figure 3 is a perspective view of a portion of a machine of a well knowncharacter having the improved thread carrying looper, throat plate andneedle arrangement embodied therein;

Figure 4 is a perspective View of the stitching elements shown in Figure3 and showing the threadin of said elements and the hemmed seam formedthereby;

Figure 5 is a view similar to Figure 4, but showing a differentcombination of stitching elements Figure 6 is a perspective view ofthejimproved throat plate and stitch fingers carried thereby.

The invention is directed broadly to a hemmed seam for fabrics, aprocess for making said seam, and certain new machine elements forcarrying out said'process. The hemmed seam includes in the broadestaspect of the invention a row of thread loops which are passed throughthe material which is to have a hemmed seam formed thereon back from theedge of the fabric and parallel with which in infolded as indicated F.

said edge. The fabric is preferably folded between this row of stitchesand the edge of the fabric back upon itself, thus forming a hem in thefabric. This hem is secured by upper and lower covering loops which inturn are concatenated with the penetratin thread loops. In order toprevent the edgeof the fabric folded back from protruding or penetratingthrough the covering threads the upper covering threads which lie on thefolded over edge of the fabric are formed in groups laid flat againstthe fabric so that in effect each covering loop consists of a pluralityof flatly nested thread loops. This gives more body to these coveringloops which insures the covering of the edge of the fabric and any looseprojecting thread ends contained there in. In order to firmly attach thecovering threads and the penetrating loops to the material even thoughthe hem is very narrow, it is preferred to lay in the covering loops anadditional thread loop which extends further inwardly from the edge ofthe material and is secured by a separate row of penetrating loops whichmight be termed anchoring loops. It is understood, of course, that thepenetrating loops are secured to the under or lower face of the fabricby a thread loop which extends to the edge of the fabric where it isinterlocked with the covering thread loops or said penetrating loopsthemselves may be carried to the edge of the fabric and thereinterlocked with the covering threads which form the covering loops forthe upper face of the fabric.

Referring to Figure 1 of the drawings, there is shown therein a fabricF, the edge of A. row of thread loops i are passed through the fabric Fjust inside of the edge of the folded in portion F. In Figure 4 of thedrawings, the process and machine for forming the renamed seam shown inFigure 1 are illus trated and possibly the hemmed seam will be betterunderstood by reference to this Figure 4:, and also to Figure 3, inconnection with the ClGSCllPtlOHOf the seam. This hemmed seam ispreferably made on the sewing machine which is provided with two needles0 and p.

and the directionof the feed.

These needles are mounted in the usual needle barreciprocated in theusual way. The two needles are set in a plane which is obliquelyarranged relative to the edge of the material Thus it is that theneedles are staggered so that the penetrating loop formed by one needlewill be in rear of the penetrating loop formed by the other needle.Cooperating with these needles 0 and p is a looper Z which is of thethread carrying type. The thread of this looper isin- 'dicated at Z. Thelooper is so set as to pass into both of the needle thread loops beneath"the material as clearly shown in Figure 4.

Cooperating with this looper Z is a thread carrying looper-a. Saidlooper a has the ordidrawings.

nary thread guide a at the heel thereof. The looper is also providedwith a group of eyes 0 near the front end of the looper. These eyes 0are arranged one above the other. The cov ering threads 7 pass throughthe guide a and then through the eyes 0 there being one covering threadfor each eye. While there has been shown three thread eyes 0 it will beunderstood, of course, that the number of thread eyes may be varied. Atthe extreme forward end of the looper there is another thread eye orgroup of eyes 6. These eyes Z) and c are set a sufficient distance apartso that the needle 0 will pass into the thread loopsof the threadspassing through the thread eyes 0 and also into the thread loop of thecovering threads passing through the eyes 6. The needle p, however, willpass into the covering loops formed by the threads passing through thetiread eyes I) of the looper only.

After the looper Zhas passed through the needle thread loops beneath thefabric, it moves to a point where the looper a will pass through theloop formed in the thread Z. This causes the upper and lower coveringthread loops to be interlocked at the edge of the fabric as shown in thedrawings. The threads carried by the looper a are locked or held by theneedle thread loops after the manner thus described. The covering threadloops f'extend over the folded in portion of the material and aresecured by the needle thread i. The covering threads, however, passingthrough the eyes I) of the looper a will pass on through the loops inthe needle thread i and will be secured by the loops in the needlethread is. The eyes 0 of the looper a are so arranged that the loops inthe covering threads passing through these eyes will lie nested togetheron the face of the ma terial as clearly shown in Figure '1 of the Thecovering thread 9 which is the thread passing through the eye 6 of thelooper extends to a point where it is secured by'the anchoring threadloops 70. By this nesting of the covering thread loops a very efficientcovering is formed for the turned in portion of the material. Eventhough the edge of the material be a raw cut edge the ends of the threadwill be held down and will not protrude above the face of the coveringthreads. This hemmed seam is especially adapted for theiedging of pockethandkerchiefs or similar goods where it is desired to make the hem orturned in portion very narrow. In the finished article the turned inportion is not only very well covered but the covering thread portionsare also anchored and securely fastened to the edge of the fabric.

In the preferred form of the machine there is a throat plate Q havingthe usual feed slots formed therein. Said throat plate is also providedwith a removable section 1" which is secured to the main section of thethroat its (ill

plate by means of the screws 8 passing through slots in the section 1"and screwed into the main part of the plate. This section 1', forms onewall of the inner feed slot and also the inner wall of the recess orthroat in which the looper operates from beneath the material. It isprovided with a stitch finger t which tapers toward the free end thereofand this stitch finger lies outside of the needle so that the coveringthreads carried by the loopers will be interlocked over this stitchfinger and will slide off from the finger when the feed fabric takesplace. By adjusting the section a" of the throat plate the stitch fingermay be moved further beyond the needle and thus properly positioned forsupporting the threads during the interlocking of the covering threads.The section 1 of the throat plate is also provided with a slot to whichextends the entire length thereof and is parallel with the edge of thesection 4 and parallel with the longitudinal axis of the stitch finger.Located in this slot to is another finger n which extends between thetwo needles and helps to support the threads and the edge of the fabricduring the laying of the covering threads. This stitch. finger u islikewise adjustable in an end-wise direction and is held in the slot andin its adjusted positions by a headed screw '0 threaded into the section0" and overlying said finger.

This throat plate is provided also with an outwardly extending andinwardly curved lip which in a sense is a part of the stitch finger t.This member, however, operates as a hem folder for turning the edge ofthe material back onto the body portion thereof as the terial is fedinto the machine. This member operates in the well known manner in theconnection with the forming of hemmed seams.

In Figure 2 of the drawings there is shown a slightly modified form ofthe hemmed seam in that the covering thread 9 has been omitted otherwisethis hemmed seam is precisely that shown in Figure 1 and is made in thesame manner as described above.

In Figure 5 of the drawings there has been shown a slightly modifiedarrangement of the stitching elements. In this form of the invention theneedle 39 is omitted. The lower looper indicated at S is a known threadcarrying looper and said looper or spreader merely carries the needlethread loops of the needles above the edge of the fabric sufiiciently sothat said loop may be locked by the upper thread carrying looper. threadcarrying looper as shown in this figure and indicated at his likewise ofa well known type except that it has been changed so as to provide aseries of thread eyes 0 for handling the covering threads It isunderstood, of course, that this looper it passes through the needlethread loop 21 which is carried and The upper held positioned by thespreader S so that said looper k can pass into the same. In this form ofthe invention there are no anchoring covering threads but the coveringthreads laid are formed into a series of nested loops lying flat side byside on the hemmed seam.

It will be understood from the above description that not only a newhemmed seam has been formed but a new process of forniing hemmed seamswhereby a resulting seam operates to more efiiciently cover and protectthe hemmed edge of the material and the threads of the hemmed seam areefiicienth anchored in the material although the turned over portion ofthe fabric is extremely narrow. It will be understood that from certainaspects of the invention tiie concatenation of the threads and theanchoring of the same which has been described in detail particularlythe nesting of the covering threads may he uset for forming an overseamor edge-covering without any hemming or infolding of the material. Theinner stitch tongue it is likewise tapered so that the thread loops willreadily slip oii' from the end of the same when the feed takes place.These tongues may be independently adjusted and v are adjusted whenfound necessary in connection with the changing in the length of thestitch and, of course, when said tongues wear away. These tongues may bereadily removed and others substituted therefor as they wear while thethroat plate is exposed to very much less wear. While the looper for thecovering threads has been described as having an eye adjacent the pointthereof, it will be understood that a plurality of eyes may be formed atthe point and arranged one above the other so as to form nested coveringthreads which likewise perform the function of anchoring the seam.

Having thus d scribed my invention, what I claim as new and desire tosecure by Letters Patent, is

1. A" hemmed seam comprising a fabric, two parallel rows of independentthread loops spaced from each other and spaced from the edge of thefabric, covering threads for the edge of the fabric including a seriesof nested thread loops which are locked by each penerating thread loopin the row adjacent the edge of the fabric, and an independent cover ingthread loop nested about said covering thread loops and extendingunderneath the thread forming tne outer row of th ead loops and securedby the inner row of thread loops whereby said covering loops areanchored and firmly secured to the fabric.

2. A l emined comprising a fabric,

two parallel rows of independent thread loops thread loops which arelocked by each pene trating thread loop in the row adjacent the edge ofthe fabric, and an independent covering thread loop nested about saidcovering thread loops and extending underneath the thread forming theouter roW of thread loops and secured by the inner row of thread loopswhereby said covering loops are anchored and firmly secured to thefabric, said fabric between the outer row of thread loops and the edgethereof being infolded so as to be covered by said nested thread loops.

3. An overedge seam for fabrics comprising two parallel rows ofindependent needle thread loops spaced from each other and spaced fromthe edge of the fabric, covering threads for the edge of the fabricincluding a series of nested thread loops which are locked by thepenetrating thread loops in the row adjacent the edge of the fabric, andan independent covering thread loop nested about the covering threadloops and extending underneath the thread forming the outer row ofthread loops and secured by the inner row of thread loops, and a row ofunder thread loops securing the needle thread loops and secured by thenested covering thread loops.

In testimony whereof, I aihx my signature.

KARL MAIER.

